1. Field of the Invention
This invention is directed to novel vinyl sulfonate polyalkylene oxides as well as to solid electrolytes derived by polymerization of such vinyl sulfonate polyalkylene oxides.
2. State of the Art
Electrolytic cells containing an anode, a cathode and a solid, solvent-containing electrolyte are known in the art and are usually referred to as "solid batteries". These cells offer a number of advantages over electrolytic cells containing a liquid electrolyte (i.e., "liquid batteries") including improved safety features.
The solid, solvent-containing electrolyte employed in such solid batteries contains either an inorganic matrix or an organic polymeric matrix as well as a suitable inorganic ion salt. Because of their expense and difficulty in forming into a variety of shapes, inorganic non-polymeric matrices are, however, not preferred and the art typically employs a solid electrolyte containing an organic or inorganic polymeric matrix.
Suitable organic polymeric matrices are well known in the art and are typically organic homopolymers obtained by polymerization of a suitable organic monomer as described, for example, in U.S. Pat. No. 4,908,283 or copolymers obtained by polymerization of a mixture of organic monomers. Suitable organic monomers include, by way of ethylene oxide, propylene oxide, ethyleneimine, epichlorohydrin, ethylene succinate, and an acryloyl-derivatized polyalkylene oxide containing an acryloyl group of the formula CH.sub.2 .dbd.CR'C(O)O-- where R' is hydrogen or lower alkyl of from 1-6 carbon atoms.
One problem associated with the polymerization of certain organic monomers is that rather strong conditions are required to effect the desired degree of polymerization. The strong conditions used, in turn, can have an adverse effect on the partially manufactured battery components treated under these conditions. Accordingly, the art has been searching for organic monomers which are readily polymerized and which, when polymerized, form suitable solid polymeric matrices for use in preparing solid electrolytes.
Additionally, suitable organic monomers preferably contain at least one hetero atom capable of forming donor acceptor bonds with inorganic cations (e.g., alkali ions). When polymerized, these compounds form a polymer suitable for use an ionically conductive matrix in a solid electrolyte.